The extensible perforate floor mat and friction device of the M. Kessler U.S. Pat. No. 3,703,059 has achieved immense success not only in the United States, but also abroad. It meets the needs for which it was originally designed, such as those expressly mentioned in said U.S. Pat. No. '059. Such a mat as disclosed in said '059 patent consists of a first series of equally spaced ribs held together by a second series of equally spaced supports molded below and at 90.degree. to the first mentioned ribs. The spaced apart ribs of this mat provide a built-in drain for run off water. The upper spaced ribs support and scrape the shoes passing thereover. The construction provides a degree of softness to ease the load on tired feet and reduce the road shock of walking.
Other grid-like floor mats are known in the patent literature, and some combination mats including fibrous materials provided in certain areas are also known. There may be briefly mentioned the U.S. Pat. Nos. 3,808,628; to Betts Liberatore 2,436,315; Watti 910,332; Roullier 164,333; and Smith 2,777,789. These patented mats, however, suffer from a number of disadvantages including difficult and/or costly manufacture, insufficient cushioning, and/or poor wear properties, i.e. short lifetime; these deficiencies are not present in the mat of the aforementioned U.S. Pat. No. '059.
However, the mat of Kessler '059 does have certain deficiencies which have become apparent over the years. Thus, in wet applications ribs alone cannot scrape clean a wet shoe. Also, "spike" heels may begin to penetrate between the spaced upper ribs at a point roughly mid-distant between the spaced lower ribs, and as soon as this begins to happen the upper ribs may begin to spread apart so that the spike heel become wedged therebetween.